Duet: File Transfer & Share

Duet moves what matters from one phone to another — and gets out of your way. Pick a file, a contact, a Wi-Fi password, a 2FA setup code, or any text. The sender shows a QR code; the receiver scans it. For larger files, the two phones connect directly over your local Wi-Fi network and the file streams across — no upload, no size cap. Everything is end-to-end encrypted, and nothing ever touches a server. No account. No sign-up. No cloud. No cross-app tracking. WHY DUET • Reliable by design — built to finish the transfer, every time. • Truly private — your data goes phone-to-phone, never through us. We can't see it, because it never reaches us. • Calm — no upsells and no "create an account" wall. Duet is free, supported by small, non-personalized ads (no advertising ID, no cross-app tracking). WHAT YOU CAN SEND • Files of any kind — documents, photos, videos, archives. Streamed directly, so size isn't a problem. • Wi-Fi credentials — share your network without reading the password aloud. • Contacts — send a contact card that drops straight into the other phone. • 2FA / authenticator setup codes — move your TOTP seeds to a new phone. • Plain text and links. HOW IT WORKS • Small items travel in a single QR code — scan and done, no network needed. • Larger items use an animated QR sequence or a direct local-network link between the two phones. Your data stays on your local network; it never goes to the cloud. • Every transfer is end-to-end encrypted. For local-network mode, both phones pair securely — scan each way and you're done, with no code to compare. PRIVATE BY DESIGN • Your transfers never reach us — phone-to-phone, end-to-end encrypted, and their contents are never written to permanent storage. • No cross-app tracking and no profiling. Ads are non-personalized — no advertising identifier (IDFA / Android Ad ID). • To keep the app stable and improve it, Duet uses Google Firebase for crash reports and anonymous, aggregate usage — only after you consent, and you can decline or turn it off any time in Settings. It never includes what you send. Works phone-to-phone across iPhone and Android. iOS 15+ and Android 8+.